Improvement in pneumatic dredging-tubes



4 W. P. LEWIS.

,Pneumatio Dredging Tube., No. 216,686. Patented Ju'ne17.18 79.

WITNESSES: I I INVENTOR:

ATTORNEYS.

NPETFJIS, PIOfOLUTHOGRAPMER, WASHINGTON, 0 6.

UNITED STATES PATENT OFFICE.

WILLIAM P. LEWIS, or OROVILLE, CALIFORNIA;

IMPROVEMENT IN PNEUMATIC DREDGING-TUBES.

Specification forming part of Letters Patent No. 216,686, dated June 17, 1879; application filed December 12, 1878.

To all whom it may. concern:

Be it known that I, WILLIAM P. Lewis, of Oroville, in the county .of Butte and State of California, have invented a new and Improved Pneumatic Dredging-Tube, of which the following is a specification.-

The object of this invention is to provide an improved dredging apparatus for clearing out rivers and harbors, and for mining and other purposes.

- It consists in raising the solid matter by creating a vacuum in the tube, and expelling it from the vacuum-chamber by the assistance of the direct aption of steam; and the apparatus for doing this is composed of a tube with steam and water supply pipe at the top, and inlet and outlet valves at the bottom, the said pipe being connected bya ball-and-socket joint with a second pipe, and this in turn is telesooped in a third pipe that bearsupon the bottom to be dredged, and in the lower part of this pipe is a water-pipe connected with a steam-pump, which, by injecting a stream of water upon the solid material, loosens it, so

- that it is readily forced up into the dredgingtube.

In the accompanying drawing a vertical longitudinal section of my improvement is shown.

Similar letters of reference indicate correspondin g parts.

Referring to the drawing, A- represents the tube forming the vacuum-chamber. The upper end is closed and provided with a steam and water pipe, a. The lower end of the chamber is provided with a valve, b, hinged at one end to the side of the chamber, while the free end lies against the opposite side in an inclined position, and is controlled by a flat spring, a, fixed at one end to the wall of the chamber, while the free end bears upon the upper side of the valve, and serves to keep it down, thus closing the bottom of the chamber.

In line with valve b, and opposite its upper side, is an opening, 01, in the wall of the chamber, closed by a vertically-hung door, 6, which is designed to be lined with india-rubber, forming a packing, so that it will cover tightly the opening d, making it as nearly as possible airtight.

The end of tube A is connected, by a balland-socket joint, B, with another tube, (3, and this in turn is telescopediu the tube D, which slides freely up and down on the former; it being designed to rest on the bottom or place to be dredged, and to accommodate itself to the unevenness of the surface on which it rests.

E represents a hydraulic pipe leading from a steampump to the lower end of pipeD and into the interior thereof. By means of this pump water is forced through pipe E against the solid matter to be dredged, looseuingit, so that it can be readilycarried upward by the pressure exerted upon the water.

The operation of my'improvement is as follows: Tube or vacuum chamberA is fixed to the bow of the dredging-boat, with tubes 0 and D hanging downward. Pipe a is connected with a steam and water supply, and hydraulic pipe E with a steam-pump. Steam is turned into chamber A through pipe at, and when it is full is cut off and water turned in sufficient to condense the steam. This creates a vacuum, and the solid material under tube D is forced up through pipes I) and O, and, opening valve 1), enters the chamber A, filling the same, and by its weight closing the valve. Steam is again turned into chamber A, and the material therein pressing against door a forces it open, and the material is delivered out of the same, the pressure of the steam on top accelerating its delivery. As soon as the chamber is empty the door 6 closes, and the steam again filling the chamber is condensed, and the operation is repeated as before.

In practice there can be two vacuumchambers, A, with valves and supply-pipes work ing alternately, so that when one is expelling 'the material from its chamber the other is condensing and forming a vacuum. Thus a continuous discharge can be maintained;

The water forced through pipe E, being pro jected with great force against the places to be dredged, loosens the material and cuts it out, so that it yields readily to the pressure of the water.

There may be separate pipes at the top of vacuum-chamber A for the steam and water, if desired.

Having thus described my invention, I

claim as new and desire to secure by Letters! material to the chamber and delivering the Patent same, the tube 0, connected with tube A by 1. As an improvementin pneumatic dredges, ball-and-socket joint B, and tube D, telescoped the vacuum-chamber A, in combination with on tube 0, and provided With hydraulic pipe steam and Water supply pipe at, valves 1) 0, and E, connected with a steam pump, substantubes 0 D, substantially as described. tially as and for the purpose described.

2. As an improvementiu pneumatic dred ges, the combination and arrangement of the tube WILLIAM PERRY LEWIS A, forming a vacuum-chamber, provided with Witnesses: pipe at, for supplying steam and Water, and the LEON D. FREER, valves 1) e, for regulating the admission ofthe i JOHN J. SMITH. 

